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Autism is a developmental disability with age of onset in childhood (under 3 years old), which is characterized by definite impairments in social interactions, abnormalities in speech, and stereotyped pattern of behaviors. Due to the progress of autism in recent decades, a wide range of studies have been done to identify the etiological factors of autism. It has been found that genetic and environmental factors are both involved in autism pathogenesis. Hence, in this review article, a set of environmental factors involved in the occurrence of autism has been collected, and finally, some practical recommendations for reduction of the risk of this devastating disease in children are represented.

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ObjectivesTo explore the association between ACE gene insertion/deletion (I/D) polymorphism with left ventricular hypertrophy (LVH) in patients with hypertension who have developed heart failure with preserved ejection fraction (HFpEF). Being a major contributor to the development of diastolic heart dysfunction, the renin angiotensin aldosterone system and its genetic variations are thought to induce LVH in hypertensive hearts apart from haemodynamic factors.DesignCase control study.SettingAn Iranian referral university hospital.Participants176 patients with hypertension and a diagnosis of HFpEF on presence of symptoms of heart failure plus Doppler echocardiographic documentation of left ventricular (LV) diastolic dysfunction and/or elevated NT-proBNP levels. Those with significant coronary, valvular, pericardial and structural heart diseases were excluded as well as patients with atrial fibrillation, renal failure and pulmonary causes of dyspnoea. They were divided into two cohorts of 88 cases with and 88 controls without LVH, after determination of LV mass index, using two-dimensional and M-mode echocardiography. The I/D polymorphism of the ACE gene was determined using the PCR method.ResultsThe D allele was significantly more prevalent among cases with compared with controls without LVH (p=0.0007). Genotype distributions also differed significantly under additive (p=0.005, OR=0.53, 95% CI 0.34 to 0.84) and recessive (p=0.001, OR=0.29, 95% CI 0.13 to 0.66) models.ConclusionsIn patients with hypertension who develop HFpEF, the D allele of the ACE gene is probably associated with the development of LVH. With the detrimental effects of LVH on the heart's diastolic properties, this can signify the role of genetic contributors to the development of HFpEF in patients with hypertension and may serve as a future risk predictor for the disease.

Among fibers with lignocellulosic origin, Kenaf fiber, because of its advantages and as a sustainable alternative to synthetic fibers has received increasing attention for manufacturing hybrid composites with reasonable acoustical and physical properties. The present study deals with the impact of chemical treatment of Kenaf fibers on the overall properties of hybrid composites fabricated from these fibers. Also, the results from predictive analytical model of sound absorption for these composites were employed for comparison with the experimental findings. Kenaf fibers were treated at room temperature with 6% concentration of sodium hydroxide (NaOH) and 4 h immersion time. Having manufactured the composites with the treated and untreated fibers, the normal sound absorption coefficients and tensile strength properties of these sample composites were determined according to ISO 10534-2 and ASTM C1557 − 14, respectively. The SEM analysis of the treated and untreated fibers revealed that in terms of fiber diameter and morphology the former was thinner and had better surface appearance. The experimental measurement of acoustic absorption coefficients of the composites made of treated fibers demonstrated superior sound absorption properties and tensile strength. The revised empirical models proposed by Delany & Bazley and Garai & Pompoli along with Nelder-Mead simplex method were employed and well predicted the sound absorption coefficients of the sample composites. There was also a fair consistency between the experimental and predicted results.

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One of the major problems associated with the electrospun scaffolds is their small pore size, which limits the cellular infiltration for bone tissue engineering. In this study, the effect of increasing the pore size on cellular infiltration was studied in poly/nanohydroxyapatite electrospun scaffolds, which were modified using ultrasonication, co-electrospinning with poly (ethylene oxide), and a combination of both. Ultrasonic process was optimized by central composite design. The ultrasonic output power and time of the process were considered as the effective parameters. The pore size of the scaffolds was evaluated by scanning electron microscope. The optimum conditions, according to the pore area and mechanical properties of the scaffolds were selected, and finally the groups that had the highest pore size and mechanical strength were selected for the combined method. Increasing the pore size enhanced the cellular proliferation, extension and infiltration, as well as the osteodifferentiation of stem cells. At the optimum condition, the average cellular infiltration was 36.51 µm compared to the control group with no cellular infiltration. In addition, alkaline phosphatase activity and the expression of osteocalcin and collagen I (COL I) were, respectively, 1.86, 2.54, and 2.16 fold compared to the control group on day 14. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1887-1899, 2017.